Use osgDB::Registry::instance()->writeNode(...) in runtime

[FuXiii]

1. use a = readNodeFile("./model.ive") read a file, then add a into root node
2. open the viewer to see the model in osg
   
3. use UpdateCallback wait to write node a into output.ive file:

//UpdateCallBack
void Update()
{
    if (this->isWirte) 
    {
        osgDB::ReaderWriter::WriteResult result = osgDB::Registry::instance()->writeNode(*a, "output.ive", osgDB::Registry::instance()->getOptions());
        if (result.success()) 
        {
            std::cout<<"writeNodeFile::Success"<<std::endl;
        }
        else
        {
            std::cout<<"writeNodeFile::Failed"<<std::endl;
        }

        this->isWirte=false;
    }
}

4. set bool isWirte to true and write node a into output.ive, then Cmd windows shows:
   

5. read the output.ive back into osg, the model become White model, looks like losted textures.
   

---

now I had tested:

1. use osgDB::ReaderWriter::Options::setOptionString("WirteImageHint=include") or osgDB::ReaderWriter::Options::setOptionString("WirteImageHint=<include>") didn't fixed this issue.
2. move wirte code from UpdateCallback to Before osgViewer::Viewer::frame(...)

void WindowUpdateOrGameLoop()
{
        //here write ive node file before call osgViewer::Viewer::frame(...)
        wirteNodeFile();
        ...
        osgViewer::Viewer::frame(...)
} 

didn't fixed this issue.

---

If I call write osgDB::Registry::instance()->writeNode(...) before I show the osgViewer (maybe osgViewer::run()) it will write correctly. and read back output.ive will show correctly with right texture.

How to write correctly when osg at Runtime?

[robertosfield]

Could you try changing the file format your write out and read back from to .osgb rather than the very old .ive format.

Also try using osgconv to convert the files i.e.

osgconv originalfile.ive newfile.ive
osgconv originalfile.ive newfile.osgb

Then try running:

osgviewer newfile.ive
osgviewer newfile.osgb

[FuXiii]

I had fixed this problem by my net group friend.
After read model file into OSG, traverse all model's children node stateset an call:

osg::Texture2D* tex2D = dynamic_cast<osg::Texture2D>(stateset->getTextureAttribute(i, osg::StateAttribute::TEXTURE));
tex2D->setUnRefImageDataAfterApply(false);

And then call osgDB::Registry::instance()->writeNode(...) and then read the writed model file. It will draw correctly.
I don't know weather this the right method to fix this issue, if only look at the result, it maybe the right way.